Income Taxes (Tax Credit Carryforwards) (Details) - Federal [Member] $ in Millions	Dec. 31, 2018 USD ($)
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	$ 29.5
Research and Development Credit [Member]
Tax Credit Carryforward [Line Items]
Tax credit carryforward	$ 8.6

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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